210 ILLIQITIMATB OFFSPRING OF Chap. V. 



very fair result may thus be gained. As, however, the 

 maximum number observed in the twenty-five capsules 

 of the short-styled form was low, the standard in this 

 case may possibly be not quite high enough. But it 

 should be observed, in the ease of the illegitimate 

 plants, that in order to avoid over-estimating their in- 

 fertility, ten very fine capsules were always selected; 

 and the years 1865 and 1866, during which the plants 

 in the three latter classes were experimented on, were 

 highly favourable for seed-production. Now, if this 

 plan of selecting very fine capsules during favourable 

 seasons had been followed for obtaining the normal 

 standards, instead of taking, during various seasons, 

 the first capsules which came to hand, the standards 

 would undoubtedly have been considerably higher; and 

 thus the fact of the six foregoing plants appearing 

 to yield an unnaturally high percentage of seeds may, 

 perhaps, be explained. On this view, these plants are, 

 in fact, merely fully fertile, and not fertile to an ab- 

 normal degree. Nevertheless as characters of all 

 kinds are liable to variation, especially with organisms 

 unnaturally treated, and as in the four first and more 

 sterile classes, the plants derived from the same par- 

 ents and treated in the same manner certainly did 

 vary much in sterility, it is possible that certain plants 

 in the latter and more fertile classes may have varied 

 so as to have acquired an abnormal degree of fertility. 

 But it should be noticed that, if my standards err in 

 being too low, the sterility of all the many sterile 

 plants in the several classes will have to be estimated 

 by so much the higher. Finally, we see that the ille- 

 gitimate plants in the four first classes are all more 

 or less sterile, some being absolutely barren, with one 

 alone almost completely fertile; in the three latter 

 dasses, some of the plants are moderately sterile. 



